package com.example.filepersistencetest.SQLiteUtil

import android.content.Context
import android.database.sqlite.SQLiteDatabase
import android.database.sqlite.SQLiteOpenHelper
import android.widget.Toast

class MyDatabaseHelper(
    private val context: Context?,
    name: String?,
    version: Int
): SQLiteOpenHelper(context, name, null, version) {
    private val createBook = "create table Book (" +
            " id integer primary key autoincrement," +
            "author text," +
            "price real," +
            "pages integer," +
            "name text)"
    private val createCategory = "create table Category ("+
            "id integer primary key autoincrement,"+
            "category_name text,"+
            "category_code integer)"
    override fun onCreate(db: SQLiteDatabase) {
        db.execSQL(createBook)
        db.execSQL(createCategory)
        //Toast.makeText(context, "创建成功！", Toast.LENGTH_SHORT).show()
    }

    override fun onUpgrade(db: SQLiteDatabase, oldVersion: Int, newVersion: Int) {
        db.execSQL("drop table if exists Book")
        db.execSQL("drop table if exists Category")
        onCreate(db)
    }

}